Status setting is performed by setting a predetermined value in a status register equipped in a playback apparatus. There are three methods for setting a value in a status register, namely, a method of setting according to static information recorded on a recording medium, a method of setting dynamically according to a command recorded on the recording medium, and a method of setting according to a predetermined procedure by a program preinstalled in the playback apparatus.
The setting method that uses the preinstalled program does not involve the author, and therefore there is no freedom to change the value of the status register in accordance with the contents of video recorded on the recording medium. Thus, this method cannot reflect ideas of the author.
The static setting method enables a value corresponding to the contents of video subjected to playback, to be set in the status register. However, once the static information has been written on the recording medium, the status register is set according to this static information irrespective of which condition the playback apparatus is in. Thus, this method lacks flexibility to change the value of the status register according to the operation of the playback apparatus.
The setting method according to a command string recorded on the recording medium enables an appropriate value to be set in the status register depending on variable factors such as what operations the user has made so far and which path the playback has taken to play back a digital stream. This allows the author to reflect its ideas. According to this method, however, the author needs to perform a programming debug test to ensure normal setting operations, which increases the burden on the author.
The need for a debug test causes a heavy burden on authors that produce movies with limited capital, though this may not be the case with large production companies. Such a burden could adversely affect content production that is the core business of the author.